Protein-Sparing Modified Fast (PSMF) Guidelines
|This diet is good for:
• Rapid fat loss
• Seeing results and building motivation
|This diet is NOT good for:
• Long-term wellness
• Increasing energy
• Boosting metabolism
• Athletic performance
• Building muscle
• Strength gain
A protein-sparing modified fast (PSMF) is a very low-calorie diet (less than 1,000 calories per day) that involves significantly limiting the intake of calories, carbohydrates, and fat while increasing protein consumption. This is a temporary diet designed to kick-start rapid fat loss. The idea of a PSMF is to reduce calories to the lowest possible threshold while still eating enough protein to preserve lean muscle mass and taking in enough key micronutrients to avoid deficiency. A PSMF should only be used for up to eight weeks before transitioning back to a sustainable long-term GRx diet.
Allowed foods (eat as much as you are hungry for):
- Lean red meat: all lean cuts of beef (no ribs and rib eye), veal, buffalo, venison, ostrich
- Organ meats: liver, kidneys, heart, tongue
- All poultry, except duck and goose (but without skin)
- Lean pork
- All fish: fatty, lean, white, oily, raw, or cooked
- All shellfish
- Nonfat dairy products (if tolerated)
- Non-starchy vegetables, raw or cooked
- Amaranth or Chinese spinach
- Artichoke hearts
- Baby corn
- Bamboo shoots
- Beans (green, wax, Italian)
- Bean sprouts
- Brussels sprouts
- Cabbage (green, bok choy, Chinese)
- Coleslaw (packaged, no dressing)
- Greens (collard, kale, mustard, turnip)
- Hearts of palm
- Salad greens (chicory, endive, escarole, lettuce, romaine, spinach, arugula, radicchio, watercress)
- Squash (cushaw, summer, crookneck, spaghetti, zucchini)
- Sugar snap peas
- Swiss chard
- Water chestnuts
- Yard-long beans
- Extras: coffee, tea, vinegar, natural flavorings, spices, herbs, pickles, sauerkraut, lemon, salt, mustard (gluten-free)
- Aim for a daily intake of 1 gram of protein per pound of bodyweight
- Eat at least one pound of fatty fish per week (salmon, sardines, mackerel, herring) to ensure adequate omega-3 intake
- Drink half your body weight in ounces of water per day. For example, if you are 200 pounds, drink 100 ounces of water a day.
- If constipation is a problem, take a prebiotic like Biotagen from Klaire Labs. Start at a small dose and build up slowly over time since prebiotics can cause gas and bloat initially.
- Consume fermented vegetables like sauerkraut, kimchi, sauerruben, and a probiotic to maintain beneficial gut flora.
- If doing PSMF for more than two weeks, take a high-quality multivitamin like Nutrient 950 with Vitamin K from Pure Encapsulations.
- Two free meals a week are permitted if necessary. This isn’t your chance to binge on junk food, but instead to eat a normal amount of carbohydrate and fat during your meal (e.g., 1-2 sushi rolls or an 8oz rib eye with sweet potato and butter).
- Average weight loss on PSMF is one pound every three to four days; some go faster, some slower.
- Do PSMF until target weight is achieved, or two months, whichever comes first. If you notice signs of significant fatigue, stop immediately.